Research for HIV Drug Resistance to Ensure the Greatest Benefit of Antiretroviral Therapy for HIV/AIDS

“HIV/AIDS has become the biggest threat to human survival in the last 700 years. Important gains made in child health and life expectancy in the Americas are being threatened by this epidemic which is destroying many of the efforts and investments of past decades.”

“In Latin America and the Caribbean, the numbers of persons estimated to be receiving antiretroviral therapy has increased from 390,000 to 445,000, an estimated increase of 55,000 persons in 2008 compared to 2007 (…). This is an impressive response from our health systems (…) and part of the comprehensive package of prevention, treatment and care that will demonstrate that WE KEEP THE PROMISE in this long battle against HIV.”

Mirta Roses Periago

Director, Pan American Health Organization

Mirta Roses confirmed increased access to ART in Latin America and the Carribean. However, have you ever heard of HIV drug resistance? How has research been fundamental in avoiding HIV drug resistance?

What’s the issue? HIV Drug Resistance: A Serious Concern in Latin America and the Caribbean

The good news is that in recent years there has been a rapid increase of ART for HIV infection in Latin America and the Caribbean. More men and women in all walks of life in need of ART have been given access to the life-saving drugs, and treatment regimens have been standardized and simplified to reflect local circumstances. Unfortunately, HIV has both a high mutation rate and high replication rate. The combination of the chronic nature of an HIV infection and the need for lifelong treatment make the emergence and transmission of HIV drug resistance (HIVDR) inevitable in populations dependent on ART. HIV drug resistance has become a serious concern in Latin America and the Caribbean.

What are the consequences of drug resistance? ART can fail, lose its medical effect. Patients whose ART has failed have to stick to second and third-line treatment successively, which are much more expensive as most of them are still under patent. Drug resistance also results in the spread of resistant strains of HIV. Failed ART means restarting complex and costly research to develop new anti-HIV drugs.

Research to Practice: Early Warning Indicators to Prevent HIV Drug Resistance

How can drug resistance be prevented? Strategies for the assessment and prevention of HIV drug resistance at the national level are being integrated as part of each country’s HIV prevention, treatment and care program. Fortunately, it is now the highest priority to monitor the ART supply and delivery within the objective to prevent HIVDR. WHO’s Global Network HIVResNet supports this monitoring process by providing standardized tools, training, technical assistance, laboratory quality assurance, analysis of results and recommendations for guidelines and public health action.

Early Warning Indicators (EWI) are used to optimize prevention of HIVDR. They serve as tools to analyze and interpret data drawn from medical and pharmacy records for a limited time period each year. Furthermore, EWI are useful for monitoring the ART supply and delivery system with the objective to optimize prevention of HIVDR. These indicators often inform national decision-making on ART programme planning and other HIVDR prevention measures.

What kind of data is collected?

• Do doctors prescribe the drugs in correct quantities?
• Do patients pick up their drugs on-time and keep clinic appointments for check-up?
• What is the percentage of patients lost to follow-up, either due to death, moving to another region or giving up treatment?
• How many people are still on first-line ART after 12 months of treatment?
• What are the trends in national ART stocks and shortages?

What next: Equitable access to medicines/Monitoring the supply and delivery system of ART

Meeting universal coverage and maintaining patients on ART is challenging, given the minimal health infrastructure, lack of trained personnel and facilities, complexities of drug ordering, delivery and storage and inadequate laboratory capacity. Achieving the best possible performance as measured by the proposed early warning indicators will help to prevent or minimize HIVDR. However, what if a country’s capacities are insufficient to provide the required data? How will we link cause to effect, considering that there may be a significant lag between the appearance of one of several indicators and the development of drug resistance?

Clearly additional research is needed to address these and other pressing questions and ensure that ART is distributed efficiently and equitably.

For more information:

• Drug resistance early warning indicators
• WHO HIV Drug Resistance Strategy